Replacing rope jammers & rig tension

[Shaun]

From: BigLofty4 (Original Message) Sent: 6/06/2005 3:25 AM
Does anyone have advice on either or both of the following problems on a Top Hat Mk3:

I need to replace the Rope Jammers/Clutches on the top of the upper deck - see attached jpeg. Whereas the winches have a panel that can be removed from the cabin ceiling, there is no obvious way to gain access to the underparts of the jammers. I can't imagine that they are just screwed into the fibreglass without some form of bolster - maybe they are!

Rig tension on a Top Hat? Has anyone any suggested tensions for shrouds, forestay etc.

Thanks
Cyril



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Recommend Message 2 of 3 in Discussion

From: GosfordPhil1 Sent: 8/06/2005 4:43 PM
Cyril
I replaced my rope jammers with ronstan clutches some time ago. I screwed them into the fiberglass with the addition of some sika flex for sealing. I have had no problems with this setup. The previous cam cleats where attached in this method and i assume that they where the origionals on the boat. As the force applied to the clutches is horozontal rather than verticle, And the screws used are the same diameter than bolts and as both are made of stainless i cannot forsee any problem. In regards to my rig tension. I had my rigging replaced last year and the rigger came out to fine tune the rigging. The main side stays where adjusted with about 1cm movement possible with the rigging unloaded. The forward lowers where then adjusted to get a small amount of aft flex in the mast. The aft lowers where then adjusted to about 50% of the main side stays. He advised max tension at all times on my back stay as i have a reef furl furler to minamise forestay wear. When sailing the leward stays lose some tension so I assume that they are not overtightened. I am not an expert on rigging setup so was relying on the riggers advice. Will follow this topic with interest
Phil

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Recommend Message 3 of 3 in Discussion

From: BigLofty4 Sent: 9/06/2005 3:08 AM
Phil,
Most helpful and much appreciated. I'll feel much better about removing the old jammers knowing that you've had no trouble. They are on so tight, I'll have to use my impact screwdriver to get them off - hope I don't crack the fibreglass!

Your advice on rig tension is very interesting. I have simply been following the manual that came with the Loos Gauge I bought. It recommends 11% of the breaking strain of the wire for most yachts, mine being 5mm diameter wire. The gauge has a graduated scale that provides % breaking strain and load in kg, which makes it very easy to set and read tension. I've just set everything to 11%, but I must check this against your rigger's recommendations. It seems to be an area where there is not a great deal of advice available, and riggers seem to carry the configurations "in their heads"! I've crewed on Hood 23s where the lee shrouds were flapping in the breeze, while on others they were tight. It would be nice to know exactly how rig tension affects performance. Anyway, many thanks for your helpful input.
Cyril